asp.net mvc disabled text box updated by javascript does not post new value

Question

I am using a strongly typed model for my view. I have a disabled text box whose value I update using javascript. The textbox is rendered using this

<%: Html.TextBoxFor(model => model.TotalAmount, new { disabled = "disabled"})%>

This renders a textbox with NAME and ID as 'TotalAmount'. TotalAmount is also a property on my model that binds to this view.

The javascript to update its value in the view is like this within its function:

document.getElementById('TotalAmount').value = {assigning new value here};

The function does get called and I can see the value in the disabled textbox when I change some value in another editable textbox. However, when I post this form to my action method as below :

[HttpPost]
public ActionResult Process (ProcessVM FormPostVM)
{
}

the disabled textbox property [TotalAmount] still has the old value but the editable textbox which I modified contains the new value I entered. Why does the disabled textbox not contain the javascript updated value?

I tried using

ModelState.Remove("TotalAmount");

in the action method above, but as I already figured it didn't work.

Any clues, tips?

Thanks for your time....

Answer 1

HTML input elements such as textboxes that have the disabled="disabled" attribute will never send their values to the server when the form is submitted. If you want to send the value to the server while still disabling the user from changing it you could make the textbox readonly:

<%= Html.TextBoxFor(model => model.TotalAmount, new { @readonly = "readonly" }) %>

Answer 2

Disabled inputs are never sent in a form submit, try using readonly attribute instead or hidden inputs

Answer 3

Disabled fields don't get posted. Try having a hidden form field that will send the value to the server, and set both TotalAmount and the hidden form field. On the server, use the value for the hidden field instead.

On a side note, since this looks like the order total, this is something I would recalcuate on the server rather than opening up the possibility of someone hacking the html and getting a discount on their product.

EDIT: To the other's points, I'd forgotten about the readonly attribute. That will work too.